The invention relates to an optical disk apparatus for enabling both of an exposed media such as a CD-ROM or the like and a cartridge enclosed media such as an optical disk cartridge with a hub or the like to be used by one drive. More particularly, the invention relates to an optical disk apparatus in which a cartridge enclosed medium is loaded as it is and an exposed medium is installed to a carrier and is loaded and also relates to a medium carrier and a medium turntable for the optical disk apparatus.
A compact disc (CD) starting from an audio-use has been remarkably developed about ten years and can presently be regarded as a primary multimedia component. Particularly, in recent years, a personal computer having therein a compact disc read only memory (hereinafter, simply referred to as a "CD-ROM") has rapidly spread. It is regarded that the position of a CD player for reproducing a CD-ROM has been established as a third file device subsequent to a floppy disk drive (FDD) and a hard disk drive (HDD). On the other hand, a rewritable type optical disk apparatus using a magneto-optical disk enclosed in a cartridge is also gradually spread by using advantages such that it has a large capacity and it is removable. The use of such a rewritable optical disk apparatus is also being progressed as a file device using a magneto-optical disk cartridge (MO cartridge) of 5 or 3.5 inches with a motor hub according to the ISO.
In a device using such a conventional optical disk media, however, an exclusive-use drive exists for every kind of the optical disk media such as CD-ROM or MO cartridge. Therefore, when the user wants to use both the CD-ROM and the MO cartridge, a CD player and an MO drive have to be separately prepared. Particularly, in recent years, in many cases, the CD player or MO drive is built in the apparatus main body as a peripheral device of a personal computer. In such a case, it is difficult in terms of the space to build two devices and there is an inconvenience such that only either one of the two devices can be built in the apparatus main body. Toward a full-scale multimedia age, with respect to the CD player, it is not limited to a function as a simple reproducing apparatus of the CD-ROM but a necessity of a rewriting function which has already been realized in the MO drive is strongly demanded. With regard to the MO drive, on the other hand, it is not limited to the use as a simple file device but it is strongly demanded that the MO drive can cope with a CD-ROM, a video CD, and the like which are provided as a part of the multimedia.
Particularly, when considering the MO drive, it is an indispensable condition to make it possible to fetch CD resources provided in the field of a personal computer which is rapidly being spread. In the CD player, in addition to a conventional CD-DA for music and a CD-ROM for reproducing dictionary data, an image data program, and the like, the edition and storage of a large capacity of data using those media simultaneously become the necessary conditions. On the other hand, the MO drive using the readable, writable, and further removable MO cartridge having a large capacity according to the ISO is also a device that is indispensable for processes of a large amount of data which is provided by the CD-ROM or the like.